Cooling Film Wrapped Articles

ABSTRACT

This invention is directed to form openings in the heat shrink film for allowing cooling air to circulate between the articles while maintaining the structural integrity of the heat shrunk film. This is accomplished by slitting the heat shrink film and forming slots between the slitted parts of the film.

FIELD OF INVENTION

This invention relates to cooling or freezing an article or a bundle of articles after the article has been filmed wrapped and heat shrunk. The term article refers to a bundle of articles such as bottles or a single article.

BACKGROUND OF INVENTION

The prior art has placed articles in cartons, having holes in the carton, to allow cold air to circulate in the carton during the freezing or cooling of the articles. This technique of cutting holes in the heat shrink film for air circulation of the article has been tried without success. Cutting the holes mechanically with an heated die or a rotating blade while the heat shrink material is moving resulted in a hole size of about ⅜ inch. Larger holes were difficult to achieve. The cooling time with these small holes impeded the cooling time for these articles. The prior art was in need of a commercial viable way of creating openings large enough to allow sufficient air circulation to cool or freeze articles with a heat shrunk film.

The prior art, shown in publication GB 2077692 shows forming slits or slots in the longitudinal direction for the insertion of labels. These machine described in this publication was sold.

An objective of this invention is to form openings in the heat shrink film for allowing cooling air to circulate between the articles while maintaining the structural integrity of the heat shrunk film.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 shows wrapping film with slots around a bundle of articles prior to heat shrinking

FIG. 2 shows separating the film into three ribbons separated by slots.

FIG. 3 shows an article wrapped with a heat shrunk film having ribbons separated by slots.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a bundle of articles 1 being pushed into a vertical plane 23 of a heat shrink film. The vertical plane 23 is formed by film 9 coming from a bottom roll 2 and film 8 coming from top roll 3. The film leaving the top roll is separated by cutting the film using an arrangement 26 described in FIG. 2.

FIG. 2 shows slitting film 8 in a longitudinal direction using cutting blades 11 and 12 to cut the film The cut film passes underneath center film guide roller 17. The center part of the film 19 passes over center film guide 18. The right separated side of the film pass between tilted side rollers 13, and 14. The left side of the separated film passes between tilted rollers 15 and 16. The placement of the tilted rollers and the degree of tilt effects the separation distance between the films. Distance between the rolls. These separated film parts can be described as ribbons. The separation between the ribbons 24 is referred to as slots. A separation of about 22 mm or larger between the ribbons are needed to achieve proper ventilation of the cooling air through the slots. Although the FIG. 3 shows 3 ribbons the apparatus can be expanded to accommodate more ribbons depending on the size of the article.

After the top film 8 has been separated into ribbons the article is transported on a conveyor and pushed through the vertical plane 23 of the film. The vertical plane is formed by the seal bar joining the film 9 from the bottom roller 2 and the separated parts of the film 8 from the top roller. The seal bar 5 comes down from behind the article to seal the film thereby enclosing the article within the film. During the sealing process the seal bar cuts the film to release the wrapped article and seals the ends of the film from the rolls to form a new vertical plane for the next bundle of articles.

The sealed wrapped bundle is transported to a heat shrink tunnel 6. After the film is heat shrunk, the wrapped article is transported to a freezer or cooler 7. The heat shrunk bundle can be bundled or palletized prior to entering the freezer or cooler.

FIG. 3 shows a film wrapped bundle of articles wherein the top film 8 is divided into three ribbons 24 separated by slots 27. Seal 25 joins the lower film 9 to the separated ribbons 8.

Although the shown embodiment has the top film separated into ribbons, the embodiment can be changed so that the lower film is divided into separated ribbons. 

1. A process for cooling an article or a bundle of articles wrapped with heat shrink film comprising, forming a slot in the longitudinal direction in at least a portion of the heat shrink film by separating the film thereby allowing cold air to circulate through the heat shrink film, film wrapping the article with the slotted film, heat shrinking the film, transporting the film wrapped article to a cooler, and cooling the film wrapped article.
 2. A process according to claim 1 wherein a slot is formed in the top portion of the wrapped article.
 3. A process according to claim 2 wherein multiple slots are formed in the film after the film is unwound from a top roll by slitting the film in the longitudinal direction to form separate film parts.
 4. A process according to claim 3 includes separating the parts of film into ribbons by forming a slot between the ribbons. 5-12. (canceled)
 13. A process for according to claim 1 wherein the slot has distance greater than about 22 mm between the separated film,
 14. An apparatus for cooling an article or a bundle of articles wrapped with heat shrink film comprising, means for forming slots in the longitudinal direction of the film in a portion of the heat shrink film so cold air can circulate through the heat shrunk film to cool the article or a bundle of articles, means for film wrapping the article with the slotted film means for transporting the film wrapped article to a cooler, and means for cooling the film wrapped article.
 15. An apparatus according to claim 14 wherein the slots are formed in the top portion of the film of the wrapped article.
 16. An apparatus according to claim 14 having means for forming multiple slots after the film is unwound from a top roll by slitting the film in the longitudinal direction to form separate film parts.
 17. An apparatus according to claim 14 including means for separating the parts of film into ribbons by forming a slot between the ribbons.
 18. An apparatus according to claim 14 including tilted guide rollers to separate the parts of film into ribbons having slots between the ribbons.
 19. An apparatus according to claim 14 wherein the slots have a distance greater than about 22 mm.
 20. A heat shrinkable film wrapped article or bundle of articles comprising, at least a portion of the wrapped film separated into ribbons having slots greater than 22 mm for cooling air circulation and, wherein the article is at a temperature of 20 degrees F. below ambient. 